Just replaced mine. (I have an 85 380). I got to the top allen head with a 1/2" allen head wrench adapter, extention and breaker handle. The most important detail here is to get the allen wrench all the way into the fastener. These bolts corrode over time and it can be difficult to get the allen wrench to bottom out in the screw. The next hurtle is to get the starter to clear the tie rods if this is the original starter. You need to have someone move the wheel one way or the other to get it out. The rebuilt MB starter I got was physically smaller.